This proposal describes the first of several planned studies to provide an evidence-based guidance to the PDGTSG in its development of a gene-transfer therapy for PD. Because Phase I studies are not designed or expected to benefit the subjects directly and because there is evidence that subjects may erroneously hope for or expect direct benefit from such studies (often called the 'therapeutic misconception ), there is considerable ethical concern about such studies. This concern is magnified for a Phase I study of gene transfer for PD because it will involve the permanent insertion of foreign DNA via a modified pathogen, introduced directly into the brain by neurosurgery. How do we know if a 'desperate' patient's willingness to take on such risks is truly valid and autonomous? This project is designed to answer that main question by answering the following set of questions: How common and how strong is that willingness'? Is that willingness reflective of a misconception; if so, how strong is the tendency to fall under such a misconception? What does an in depth examination of the motivations behind the PD patients' preferences reveal? And finally, which patient characteristics predict or explain their willingness to participate and, if applicable, their tendency to fall prey to the therapeutic misconception? This project will employ both qualitative and quantitative methods. The latter will involve a modified standard gamble technique that will allow a quantification of the strength of preferences for research participation as well as a measurement of the tendency toward the therapeutic misconception; qualitative methods will enhance validity of the preference measurements as well as provide a deeper explanatory framework for the subjects' preferences.